Describing American Catholic worship demands grappling with the broad expanse of peoples and places that have experienced the Catholic faith between the moment of the first Mass, celebrated by globe-trotting Spanish explorers in 1494, and Mass in the twenty-first century, when the first American-born pope, Francis, assumed leadership of the global church. Yet, American Catholic worship asks that we look at far more than formal ritual experiences such as the Mass, the Divine Office, or the sacraments. For much of American Catholic history, a rich panoply of devotions to Mary, Jesus, the saints, and the Blessed Sacrament played a major, if not central, role in supporting and sustaining Catholic identity on the American continent – a role that would not be challenged until liturgical renewal advocates began to question the relationship of popular piety and formal liturgical prayer in the second quarter of the twentieth century.